The {} Large Area Telescope has observed an excess of $\sim$GeV energy gamma rays from the center of the Milky Way, which may arise from near-thermal dark matter annihilation. Firmly establishing the dark matter origin for this excess is however complicated by challenges in modeling diffuse cosmic-ray foregrounds as well as unresolved astrophysical sources, such as millisecond pulsars. Non-Poissonian Template Fitting~(NPTF) is one statistical technique that has previously been used to show that at least some fraction of the GeV excess is likely due to a population of dim point sources. These results were recently called into question by Leane and Slatyer~(2019), who showed that a synthetic dark matter annihilation signal injected on top of the real {} data is not recovered by the NPTF procedure. In this work, we perform a dedicated study of the {} data and explicitly show that the central result of Leane and Slatyer~(2019) is likely driven by the fact that their choice of model for the Galactic foreground emission does not provide a sufficiently good description of the data. We repeat the NPTF analyses using a state-of-the-art model for diffuse gamma-ray emission in the Milky Way and introduce a novel statistical procedure, based on spherical-harmonic marginalization, to provide an improved description of the Galactic diffuse emission in a data-driven fashion. With these improvements, we find that the NPTF results continue to robustly favor the interpretation that the Galactic Center excess is due, in part, to unresolved astrophysical point sources across the analysis variations that we have explored.

中文翻译：

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费米银河中心多余物的前景错误建模和点源解释

{}大面积望远镜观测到过量的 $〜$来自银河系中心的GeV能量伽马射线，可能是由于近热暗物质an灭而产生的。但是，要为弥漫的宇宙射线前景以及未解析的天体物理源（例如毫秒脉冲星）建模提出挑战，就很难为这种过量物质牢固地建立暗物质起源。非泊松模板拟合（NPTF）是一种统计技术，以前已被用来证明GeV过量的至少一部分可能是由于大量的暗点源造成的。Leane和Slatyer〜（2019）最近对这些结果提出了质疑，他们表明，在实际{}数据之上注入的合成暗物质ni灭信号无法通过NPTF程序恢复。在这项工作中 我们对{}数据进行了专门研究，并明确表明Leane和Slatyer〜（2019）的主要结果可能是受以下事实的驱动：他们选择的银河系前景发射模型并未提供足够好的描述。数据。我们使用最新模型对银河中的弥漫性伽马射线发射重复进行NPTF分析，并基于球谐谐波边缘化引入一种新颖的统计程序，以提供对银河系漫射发射的改进描述。数据驱动的方式。通过这些改进，我们发现NPTF结果继续强有力地支持这样的解释，即银河系中心过剩部分归因于我们所探索的分析变异中未解决的天体物理点源。